Re: No 'slide'
Presumably you're claiming that there are seasonal variations that result in fluctuations in sales throughout the year - hence the "drop" in the recent quarter is justified. The problem is that a year ago (the year which you claim demonstrates that "they're up, not down") indicated growth throught the same period of 2011 (before a slight "dip" in sales). The graph also demonstrates growth through the same period in 2010. And 2009, and 2008.
Using my (admittedly basic, but not much worse than the analysts in the story) financial forecasting skills, one would expect, excluding unforseen market pressures, the climb to continue (maybe drop back a bit, as the story stated). Instead, they plummetted - probably due to fanbois waiting for iphone5, and also possibly Apple's customer loyalty base eroding somewhat, as people buy one of the better phones that have hit the market in recent months.
As for the analysts, applying the same rigour to the historical accuracy of predictions made by *any* analyst would probably result in them all being shot - something which, I believe, we can all agree would be a good thing.